This application claims the priority of German Patent Document 102 11 603.2, filed Mar. 12, 2002, the disclosure of which is expressly incorporated by reference herein.
The invention relates to an electrical plug connector for information technology purposes, in particular a RJ45 connector, with several contacts that are arranged in at least three contact pairs. The contacts comprise each a terminal area, a contact section for the engagement with contacts of another electrical plug connector and a line section that connects the terminal area with the contact section. The contact sections are arranged in first planes that are parallel to each other. All line sections at least in some areas run parallel to each other and in a joint second plane. The line sections and the contact sections of each contact are arranged at an angle to each other and all contacts are bent in the same direction in the transition region between line section and contact section.
From U.S. Pat. No. 5,647,770 an insert for a RJ45 connector is known where the contacts of a contact pair are crossed in a horizontal direction. The contacts, respectively, contain terminal areas for connecting cables, contact sections for the engagement with the contact sections of a matching plug and a line section connecting the terminal areas with the contact sections. The contact sections are arranged in first planes that are parallel to each other. In the transition region of the line sections to the contact sections, a bend is provided arranging the contact sections at an angle of approximately 45° in relation to the line sections. In the horizontal direction, viewed parallel to the first parallel planes of the contact sections, the crossing of the contacts from the contact pair is symmetrical. In the vertical direction, viewed vertically to the parallel first planes, the crossed contacts are arranged in different planes so that the line sections do not overlap viewed in the vertical direction.
From U.S. Pat. No. 5,399,107 an insert for an RJ45 connector is known where cross-talk at high frequencies shall be reduced by increasing the distance and employing additional dielectric material between the individual contacts. For this, the line sections of adjacent contacts are arranged in different parallel planes, and the line sections run in guide grooves made of dielectric material.
U.S. Pat. No. 5,779,503 reveals an insert for a RJ45 connector where a total of four contact pairs are provided, wherein the contacts of three contact pairs are crossed. The crossing is placed in the transition region between the line sections and contact sections of the contacts. All three crossings are identical and symmetrical. The contact sections are located in parallel first planes and all in a joint plane that is vertical to the parallel planes. The contact sections are arranged at approximately a 45° angle in relation to the line sections, which are also arranged in a joint second plane. The crossings, which are located in a transition region between the line sections and contact sections, are fastened on one side by a plastic insert.
From German Patent Document DE 198 22 630 C1, an insert for an RJ45 connector is known where the contacts of a contact pair are crossed. The contacts each contain terminal areas, line sections and contact sections. The contact sections are arranged in first parallel planes and the line sections, at least partially, in a common second plane. The transition regions between line sections and contact sections are bent in opposite directions among different contact pairs.
U.S. Pat. No. 5,911,602 reveals another insert for a RJ45 connector where two different designs of contacts, corresponding to two different contact designs, are provided. The line sections run in a joint second plane, and between the contact sections and the line sections a transitional region is arranged, respectively, which in the two different contact designs take on different designs. In the first contact design the transition region has a first angle of 90° and a subsequent second angle of about 45°. In the second contact design the transition region has a first angle of about 135°, which is followed by an angle in the opposite direction of about 45° and finally by another angle in the opposite direction of about 50°. In total, only two different contact designs are provided in this design. The two different contact designs are used within one contact pair.
International Patent Publication WO 97/19499 shows an insert for a RJ45 plug where a total of two different contact designs are provided. Within one contact pair, the same contact design is used. The two different contact designs are accomplished by ensuring that the line sections of the contacts of a contact pair do not run in one plane with the remaining line sections. In these two line sections, the transition region between line section and contact section therefore has a different design in order to arrange the contact sections in another joint plane.
European Patent Document EP 0 955 703 A2 shows an insert for a RJ45 connector where two different contact designs are provided. Within one contact pair, two different contact designs are used. The line sections of all contacts run in one joint plane. The two different contact designs are realized by offsetting a transition region between the line sections and the contact sections in a direction parallel to the line sections.
From U.S. Pat. No. 6,217,392 B1 an insert for a RJ45 plug is known where the contacts in one region, in which the distance of the contacts among each other has been enlarged in part, are embedded in a plastic block. A crossing of contacts is not provided.
An aspect of the invention relates to an electrical plug connector for information technology purposes where with a simple design cross-talk between contact pairs is reduced even in the case of high transmission frequencies.
According to certain preferred embodiments of the invention, an electrical plug connector for information technology purposes is provided, in particular an RJ45 plug, comprising several contacts that are arranged in at least three contact pairs, each containing a terminal area, a contact section for engagement with contacts of another electrical plug connector, and a line section, which connects the terminal area with the contact section. The contact sections are arranged in first planes arranged parallel to each other. All line sections run parallel to each other at least in some areas and in a joint second plane. The line sections and the contact sections of each contact are arranged at an angle to each other, and all contacts in the transition region between the line section and the contact section are bent in the same direction, where the contacts have different designs for at least two different contact pairs. The transition regions of contacts for at least two different contact pairs have different progressions from each other between the line section and the contact section in the respectively first planes. The transition regions of contacts for at least two different contact pairs are arranged at a distance from each other in a direction that is parallel to the line sections.
By designing the contacts of at least two contact pairs differently, a clear improvement in the cross-talk behavior is achieved. By equipping the transition regions of at least two contact pairs with different progressions, the transition regions of different contact pairs are not aligned with each other between the contact sections and the line sections, reducing near-end cross-talk among contact pairs. Due to the fact that all transition regions are bent in the same direction and all line sections are arranged partially in one joint plane, an arrangement with accurate dimensions and low manufacturing costs is achieved. Furthermore the transition regions of at least two different contact pairs are arranged at a distance from each other in a direction parallel to the line sections and in the joint plane. This measure also prevents that the transition regions between the line sections and contact sections of different contact pairs are aligned with each other, thus reducing cross-talk between contact pairs. Pursuant to a beneficial development three different contact designs are provided in three different contact pairs, wherein the transition regions in three contact pairs are arranged at a distance from each other in a direction parallel to the line sections and/or the transition regions in three contact pairs have different progressions.
According to a further embodiment of the invention, the contacts of a contact pair are crossed in at least three contact pairs, wherein among different contacts pairs at least two different crossing angles are selected. These measures also improve the cross-talk behavior of the electrical plug connector, especially in the case of high transmission frequencies.
Yet another embodiment of the invention, the contact sections of different contact pairs are not arranged in one joint plane with a plugged-in, matching plug connector. Due to these measures, the contact sections of different contact pairs do not align with each other, both in the non-current-carrying state and when the plug is connected with the RJ45 connector, thus positively influencing the cross-talk behavior.
In certain embodiments of the invention, the contacts are fixed in a plastic insert by embedding at least the crossings of the contacts. This way the contacts can be safely fixed. In the area of the crossings, the distance settings of the contacts to each other are adhered to accurately and also the embedding process does not change that over the life of the electrical plug connector. In particular, the pre-determined distance settings are adhered to even when the contact sections are deflected by inserting a matching plug connector. The contacts in the area of the crossings can be molded for example. Molding the contacts occurs beneficially while producing the plastic insert within one operation.
In a further development of certain preferred embodiments of the invention, the plastic insert with the contacts can be inserted into a housing, wherein the plastic insert and/or the housing contains at least one snap-fit element for fixing the plastic insert in a pre-determined position in the housing. This measure allows the plastic insert to be mounted in a plastic housing in a simple fashion and be safely fastened thereto.
In a another development of certain preferred embodiments of the invention, the snap-fit elements are arranged in the area of a guide bead or a guide groove on the plastic insert. This further facilitates accurate assembly of the electrical plug connector.
An aspect of the invention also provides a plastic insert with contacts for an electrical plug connector pursuant to certain preferred embodiments of the invention.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.